Seat Rails - Disassembly?

[Cosmicbike]

When I picked up the Laser it was somewhat damp, having been stored outside with a leaky sunroof. As a result the passenger seat rails were rusted solid. A bit of gentle persuasion moved them enough to get the seat out, and I have now got them on the bench. They are freed up OK now after a bit of work, but ideally I'd like to strip them down. I'm not able to remove the 2 sections from each other, the 2 bits that form the sliding section. It runs from one end to the other OK, but I don't know how to seperate the 2.

Any pointers please?

[Peter-S]

I think it works on sprung ball bearings so a tap with a hammer may move it along. However, go gently in case I'm wrong!